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排序方式: 共有488条查询结果,搜索用时 203 毫秒
61.
62.
Tue Trong Phan Takaaki Miyasako Koichi Higashimine Eisuke Tokumitsu Tatsuya Shimoda 《Applied Physics A: Materials Science & Processing》2013,113(2):333-338
We propose the use of a La2O3 (LO) film as the capping layer for improvement of a semiconductor/insulator interface in a solution-processed indium–tin–oxide (ITO) ferroelectric-gate thin-film transistor (FGT) device. It is demonstrated that the LO layer acts as a good barrier film not only for preventing the interdiffusion between the ITO semiconductor and lead–zirconium-titanate (PZT) insulator layers, but also for stabilizing the PZT surface structure. The fabricated FGT device exhibited high I on/I off, large M w, high μ FE and improved retention time of about 109, 3.5 V, 7.94 cm2?V?1?s?1 and 1 day, respectively, which are comparable to or better than those obtained with FGTs fabricated by means of conventional vacuum processes. We also point out that the key origin of the interface improvement is likely due to the incorporation of La into the PZT system, forming a La surface-modified PZT system which is more stable than the pure PZT in terms of Pb volatility and formation of oxygen vacancies. 相似文献
63.
Takafumi Seto Kenji Koga Hiroyuki Akinaga Fumiyoshi Takano Takaaki Orii Makoto Hirasawa 《Journal of nanoparticle research》2006,8(3-4):371-378
Monodispersed CoPt alloy nanoparticles were synthesized by a pulsed laser ablation (PLA) technique coupled with a low-pressure operating differential mobility analyzer (LP-DMA). The CoPt alloy nanoparticles were generated by laser ablating a solid Co–Pt target. In CoPt alloy nanoparticles synthesized from a target with a Co composition of 75 at%, the nanoparticle surfaces were covered by an oxide layer and exhibited a core-shell structure. In contrast, no shell was observed in particles generated from a target with a Co:Pt ratio of 50:50 at%. According to an EDX analysis, the compositions of the individual nanoparticles were almost the same as that of the target material. Finally, the magnetic hysteresis loops of the CoPt alloy nanoparticles exhibited ferromagnetism. 相似文献
64.
Hidetoshi Iwamoto Takaaki Sonoda Hiroshi Kobayashi 《Journal of fluorine chemistry》1984,26(4):535-537
Anion-catalyzed phase-transfer catalysis was successfully applied to diazotization of pentafluoroaniline in a dichloromethane-aqueous sulfuric acid two-phase system. The resulting diazonium group was coupled with anisole, 1-methoxynaphthalene, and mesitylene, and replaced with bromo, hydryl, and phenyl substituents under a two-phase condition. 相似文献
65.
Yoshinori Asakawa Tsunematsu Takemoto Masao Toyota Takaaki Aratani 《Tetrahedron letters》1977,18(16):1407-1410
The stereostructures of the two new exceptional diterpene dialdehydes from the liverwort, Trichocoleopsis sacculata: sacculatal (1), responsible for the characteristic pungent taste, and isosacculatal (2) have been determined by the spectral evidence and by comparison with polygodial (3), isopolygodial (4), and drimanediol (6) of known relative configurations. 相似文献
66.
67.
[structure: see text] An effective method for the total synthesis of 2-hydroxy-24-oxooctacosanolide, a defensive salivary secretion of the African termite Pseudacanthotermes spiniger, has been developed. The key lactonization to form a 29-membered ring lactone core is performed using 2-methyl-6-nitrobenzoic anhydride with a catalytic amount of 4-(dimethylamino)pyridine N-oxide. 相似文献
68.
Eduardo Viegas Misako Takayasu Wataru Miura Koutarou Tamura Takaaki Ohnishi Hideki Takayasu Henrik Jeldtoft Jensen 《Complexity》2013,19(1):22-36
The world economy consists of highly interconnected and interdependent commercial and financial networks. Here, we develop temporal and structural network tools to analyze the state of the economy and the financial markets. Our analysis indicates that a strong clustering can be a warning sign. Reduction in diversity, which was an essential aspect of the dynamics surrounding the financial markets crisis of 2008, is seen as a key emergent feature arising naturally from the evolutionary and adaptive dynamics inherent to the financial markets. Similarly, collusion amongst construction firms in a number of regions in Japan in the 2000s can be identified with the formation of clusters of anomalous highly connected companies. © 2013 Wiley Periodicals, Inc. Complexity 19: 22–36, 2013 相似文献
69.
Takaaki Takatsuka Hideki Tomita Tetsu Sonoda Volker Sonnenschein Chika Sakamoto Hiroki Mita Takuma Noto Chikara Ito Shigetaka Maeda Tetsuo Iguchi Michiharu Wada Klaus Wendt Iain Moore 《Hyperfine Interactions》2013,216(1-3):41-46
93Nb(n, n′)93mNb reaction allows retrospective estimation of integrated fast neutron dose in nuclear reactor. We proposed isomer-selective trace analysis of 93mNb by Resonance Ionization Mass Spectrometry (RIMS) combined with a gas-jet atomic source and an injection locked Ti:Sapphire laser system operated at several kHz. Resonant ionization spectroscopy of Nb in gas-jet using Ti:Sapphire laser was demonstrated. 相似文献
70.
Ying Xu Hosho Katsura Takaaki Hirano Vladimir E. Korepin 《Journal of statistical physics》2008,133(2):347-377
We study a 1-dimensional AKLT spin chain, consisting of spins S in the bulk and S/2 at both ends. The unique ground state of this AKLT model is described by the Valence-Bond-Solid (VBS) state. We investigate
the density matrix of a contiguous block of bulk spins in this ground state. It is shown that the density matrix is a projector
onto a subspace of dimension
. This subspace is described by non-zero eigenvalues and corresponding eigenvectors of the density matrix. We prove that for
large block the von Neumann entropy coincides with Renyi entropy and is equal to
.
NSF Grant DMS-0503712. 相似文献